在Robolectric启动期间进行反射时出现NullPointerException-有任何提示吗？

Question

我正在Eclipse上开发一个Android项目，并且试图从在模拟器/设备（ 非常
慢）上运行测试切换到Robolectric。

我用Robolectric替换了Android库，在路径中添加了JUnit，将测试用例更改回常规，TestCase并添加@RunWith(RobolectricTestRunner.class)了快速入门指南中的建议（进行必要的更改以实例化我的Activity，而不是依靠Android的活动测试来完成它为了我）。

但是，当我运行测试时，我得到：

java.lang.NullPointerException
 at com.xtremelabs.robolectric.RobolectricTestRunner.isInstrumented(RobolectricTestRunner.java:123)
 at com.xtremelabs.robolectric.RobolectricTestRunner.<init>(RobolectricTestRunner.java:72)
 at com.xtremelabs.robolectric.RobolectricTestRunner.<init>(RobolectricTestRunner.java:57)
 at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
 at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
 at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
 at java.lang.reflect.Constructor.newInstance(Constructor.java:532)
 at org.junit.internal.builders.AnnotatedBuilder.buildRunner(AnnotatedBuilder.java:31)
 at org.junit.internal.builders.AnnotatedBuilder.runnerForClass(AnnotatedBuilder.java:24)
 at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:57)
 at org.junit.internal.builders.AllDefaultPossibilitiesBuilder.runnerForClass(AllDefaultPossibilitiesBuilder.java:29)
 at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:57)
 at org.junit.internal.requests.ClassRequest.getRunner(ClassRequest.java:24)
 at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.<init>(JUnit4TestReference.java:29)
 at org.eclipse.jdt.internal.junit4.runner.JUnit4TestClassReference.<init>(JUnit4TestClassReference.java:25)
 at org.eclipse.jdt.internal.junit4.runner.JUnit4TestLoader.createTest(JUnit4TestLoader.java:40)
 at org.eclipse.jdt.internal.junit4.runner.JUnit4TestLoader.loadTests(JUnit4TestLoader.java:30)
 at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:452)
 at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
 at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
 at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)

这似乎与此代码有关（从0.9标签开始，因为0.9.1标签没有它）RobolectricTestRunner.java：

private static boolean isInstrumented() {
    return RobolectricTestRunner.class.getClassLoader().getClass().getName().contains(RobolectricClassLoader.class.getName());
}

但我不知道如何操作，因为这种思考应该从类本身开始。

另外，我可以发誓，这一次跑了多次失败面前-
我已经删除了robolectric缓存（如建议在这里），并与最新的（4.8.2）代替Eclipse中的JUnit，但什么都没有改变。

有什么提示吗？

更新：
我尝试创建一个新的Java（即普通的非Android）测试项目，如快速入门指南中所述。但是，现在测试运行会抱怨没有AndroidManifest.xml：

java.lang.RuntimeException: java.io.FileNotFoundException: /Users/chester/Documents/workspace/minitruco-android/minitruco-android-robolectric-test/AndroidManifest.xml (No such file or directory)
    at com.xtremelabs.robolectric.RobolectricTestRunner.createResourceLoader(RobolectricTestRunner.java:245)
    at com.xtremelabs.robolectric.RobolectricTestRunner.setupApplicationState(RobolectricTestRunner.java:215)
    at com.xtremelabs.robolectric.RobolectricTestRunner.internalBeforeTest(RobolectricTestRunner.java:163)
    at com.xtremelabs.robolectric.RobolectricTestRunner.methodBlock(RobolectricTestRunner.java:143)
    at org.junit.runners.BlockJUnit4ClassRunner.runNotIgnored(BlockJUnit4ClassRunner.java:79)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:71)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:49)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:46)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: java.io.FileNotFoundException: /Users/chester/Documents/workspace/minitruco-android/minitruco-android-robolectric-test/AndroidManifest.xml (No such file or directory)
    at java.io.FileInputStream.open(Native Method)
    at java.io.FileInputStream.<init>(FileInputStream.java:137)
    at java.io.FileInputStream.<init>(FileInputStream.java:96)
    at sun.net.www.protocol.file.FileURLConnection.connect(FileURLConnection.java:87)
    at sun.net.www.protocol.file.FileURLConnection.getInputStream(FileURLConnection.java:178)
    at com.sun.org.apache.xerces.internal.impl.XMLEntityManager.setupCurrentEntity(Unknown Source)
    at com.sun.org.apache.xerces.internal.impl.XMLVersionDetector.determineDocVersion(Unknown Source)
    at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
    at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
    at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(Unknown Source)
    at com.sun.org.apache.xerces.internal.parsers.DOMParser.parse(Unknown Source)
    at com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderImpl.parse(Unknown Source)
    at javax.xml.parsers.DocumentBuilder.parse(Unknown Source)
    at com.xtremelabs.robolectric.RobolectricTestRunner.findResourcePackageName(RobolectricTestRunner.java:255)
    at com.xtremelabs.robolectric.RobolectricTestRunner.createResourceLoader(RobolectricTestRunner.java:236)
    ... 18 more

我想测试应该从原始项目（minitruco-android）加载html" target="_blank">文件，该文件同时显示在测试项目的构建路径和Eclipse上的Run /
Debug构建配置中（在测试项目的classpath条目下）。无论如何，我已经复制了我原来的测试项目中的文件（只是为了测试的缘故），但随后抱怨R.java（和
那 确实应该已经从原来的项目进口）：

java.lang.RuntimeException: java.lang.ClassNotFoundException: caught an exception while obtaining a class file for me.chester.minitruco.test.R
    at com.xtremelabs.robolectric.RobolectricTestRunner.createResourceLoader(RobolectricTestRunner.java:245)
    at com.xtremelabs.robolectric.RobolectricTestRunner.setupApplicationState(RobolectricTestRunner.java:215)
    at com.xtremelabs.robolectric.RobolectricTestRunner.internalBeforeTest(RobolectricTestRunner.java:163)
    at com.xtremelabs.robolectric.RobolectricTestRunner.methodBlock(RobolectricTestRunner.java:143)
    at org.junit.runners.BlockJUnit4ClassRunner.runNotIgnored(BlockJUnit4ClassRunner.java:79)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:71)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:49)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:46)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: java.lang.ClassNotFoundException: caught an exception while obtaining a class file for me.chester.minitruco.test.R
    at javassist.Loader.findClass(Loader.java:359)
    at com.xtremelabs.robolectric.RobolectricClassLoader.findClass(RobolectricClassLoader.java:60)
    at javassist.Loader.loadClass(Loader.java:311)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:268)
    at com.xtremelabs.robolectric.RobolectricClassLoader.loadClass(RobolectricClassLoader.java:37)
    at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:336)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:186)
    at com.xtremelabs.robolectric.RobolectricTestRunner.createResourceLoader(RobolectricTestRunner.java:237)
    ... 18 more
Caused by: javassist.NotFoundException: me.chester.minitruco.test.R
    at javassist.ClassPool.get(ClassPool.java:436)
    at com.xtremelabs.robolectric.AndroidTranslator.onLoad(AndroidTranslator.java:68)
    at javassist.Loader.findClass(Loader.java:340)
    ... 26 more

我的设置和快速入门之间的唯一不同是，我将测试源保留在测试项目上，将常规源保留在常规项目上（自从首次构建以来，我就假设测试项目看到了常规源-
当然，这在很大程度上取决于）。

我正在使用SoyLatte，但也尝试了Mac
OS的默认1.6 JVM，结果相同。

谢谢。

Answer 1

通常，您不需要扩展TestCase，但是我认为这不会引起此问题。您能否包括失败测试的来源？

关于更新中的简化项目，请确保已将Eclipse配置为将当前工作目录设置为主项目的根目录，而不是测试项目的根目录，因此它将找到AndroidManifest.xml和res目录。